BETALOC DURULES TAB 200 MG TABLET (EXTENDED-RELEASE)

Country: Canada

Language: English

Source: Health Canada

Active ingredient:

METOPROLOL TARTRATE

Available from:

ASTRAZENECA CANADA INC

ATC code:

C07AB02

INN (International Name):

METOPROLOL

Dosage:

200MG

Pharmaceutical form:

TABLET (EXTENDED-RELEASE)

Composition:

METOPROLOL TARTRATE 200MG

Administration route:

ORAL

Units in package:

100

Prescription type:

Prescription

Therapeutic area:

BETA-ADRENERGIC BLOCKING AGENTS

Product summary:

Active ingredient group (AIG) number: 0111923001; AHFS:

Authorization status:

CANCELLED POST MARKET

Authorization date:

2009-12-15

Summary of Product characteristics

COPYRIGHT 1977, 2006 ASTRAZENECA CANADA INC.
PRODUCT MONOGRAPH
BETALOC
®
(metoprolol tartrate)
50 mg and 100 mg Tablets
200 mg DURULES
®
5 mL ampoule 1 mg/mL
β
-Adrenoceptor Blocking Agent
DATE OF REVISION:
SEPTEMBER 17, 2009
AstraZeneca Canada Inc.
1004 Middlegate Road
Mississauga, Ontario
L4Y 1M4
www.astrazeneca.ca
SUBMISSION CONTROL NUMBER # 130322
BETALOC
®
and DURULES
®
are trade-marks of the AstraZeneca group of companies.
- 2 -
PRODUCT MONOGRAPH
NAME OF DRUG
BETALOC
®
(metoprolol tartrate)
50 mg and 100 mg Tablets
200 mg DURULES
®
5 mL ampoule 1 mg/mL
PHARMACOLOGICAL CLASSIFICATION
β
-Adrenoceptor Blocking Agent
ACTIONS AND CLINICAL PHARMACOLOGY
BETALOC (metoprolol tartrate) is a
β
-adrenoceptor blocking agent.
_In vitro_
and
_in vivo_
animal studies have shown that it has a preferential effect on
β
1
-adrenoreceptors, chiefly
located in cardiac muscle. This preferential effect is not absolute,
however, and at higher
doses, BETALOC also inhibits
β
2
-adrenoreceptors, chiefly located in the bronchial and
vascular musculature. It is used in the treatment of hypertension,
angina pectoris and to
reduce mortality in patients with myocardial infarction.
The mechanism of the antihypertensive effect has not been established.
Among the factors
that may be involved are:
a)
competitive ability to antagonize catecholamine-induced tachycardia at
the
β
-receptor sites in the heart, thus decreasing heart rate, cardiac
contractility and cardiac
output;
b)
inhibition of renin release by the kidneys;
c)
inhibition of the vasomotor centers.
By blocking catecholamine-induced increases in heart rate, in velocity
and extent of
myocardial contraction and in blood pressure, metoprolol reduces the
oxygen requirements of
the heart at any given level of effort, thus making it useful in the
long-term management of
angina pectoris. However, in patients with heart failure,
beta-adrenoceptor blockade may
increase oxygen requirements by increasing left ventricular fibre
length and end-diastolic
pressure.
- 3 -
The mechanisms